Ball for ball game and method for manufacturing the same

Abstract

To provide a ball for ball game and a method for manufacturing the ball having superior sphericity, an ability to retain its original shape, durability, and soft feel. The fabric layer ( 12 ) is formed by sewing with a sewing machine for instance pentagonal first fabric pieces ( 13 ) together with composite shaped second fabric pieces ( 14 ) in which two hexagons are connected with each other, so that a spherical shape is formed. The marginal edge of the first and second fabric pieces are superimposed in the spherical surface direction, so that corner portions thereof are temporarily attached. Temporary attachment is achieved by inserting the needle into the needle through hole formed in the corner of the first and second fabric pieces, and welding by means of ultra sonic wave, such that the first and second fabric pieces ( 13, 14 ) are accurately aligned. The temporarily attached fabric pieces sewn together using a sewing machine along the guiding line ( 17 ) for sewing printed beforehand on the surface of the fabric pieces ( 13, 14 ).

1. Ball for ball game comprising:
 a bladder; 
 a fabric layer around the bladder; and 
 an outer skin layer made of a plurality of panels; wherein the fabric layer is formed of fabric pieces whose marginal edges are superimposed, and sewn together with a substantially radially disposed thread, 
 wherein a position of a joined portion of the fabric pieces in the fabric layer at least substantially corresponds with a position of a joined portion of the panels in the outer skin layer. 
 
   
   
     2. A ball for ball game as in  claim 1 , wherein the fabric pieces comprise a shape selected from the group consisting of a pentagon, a hexagon, and combinations thereof. 
   
   
     3. A ball for ball game as in  claim 1 , wherein the fabric pieces comprise a shape selected from the group consisting of a triangle, a pentagon, and combinations thereof. 
   
   
     4. A ball for ball game as in  claim 1 , wherein the fabric layer is formed of a laminate of two woven fabrics arranged such that respective warps of the two woven fabrics are perpendicular. 
   
   
     5. A ball for ball game comprising:
 a bladder; 
 a fabric layer around the bladder; and 
 an outer skin layer made of a plurality of panels; wherein the fabric layer is formed of fabric pieces whose marginal edges are superimposed, and sewn together with a substantially radially disposed thread, 
 wherein a shape of the fabric pieces in the fabric layer is at least substantially similar to a shape of at least one of the plurality of panels of the outer skin layer. 
 
   
   
     6. A ball for ball game as in  claim 1 , wherein at least one of the fabric pieces has a center line and at least one of a warp line and a weft line which corresponds with one of three reference circles on a spherical surface of the fabric layer, any one of the three reference circles being perpendicular to the other two reference circles. 
   
   
     7. A ball for ball game as in  claim 6 , wherein the fabric layer includes a first fabric piece arranged in such a manner that at least one of the warp line and the weft line is formed along one of the three reference circles and a second fabric piece arranged in the center of a triangular region formed by the three reference circles. 
   
   
     8. A method for manufacturing a ball comprising the steps of:
 providing a bladder; 
 forming a fabric layer around the bladder, wherein the fabric layer is formed by a plurality of fabric pieces whose marginal edges are superimposed; 
 forming an outer skin layer from a plurality of panels, wherein the fabric layer is further formed by first attaching the fabric pieces together by bonding to form a temporary attachment, and then sewing the fabric pieces together with a substantially radially disposed thread; 
 forming a spherical fabric layer by sewing the fabric pieces together by a sewing machine in such a manner as to allow an aperture not to be sewn together, the aperture serving as a hole for inserting the bladder; 
 forming a penetrating hole for inserting a needle through the fabric layer; 
 inserting the bladder into the spherical fabric layer; and 
 thereafter closing the aperture for inserting the bladder by sewing the fabric layer via the penetrating hole using the sewing machine. 
 
   
   
     9. A method as in  claim 8 , wherein the fabric pieces are sewn together along a guiding line for sewing formed on the fabric pieces by printing. 
   
   
     10. A method as in  claim 8 , wherein the fabric pieces are sewn together to form two parallel sewing lines. 
   
   
     11. A method as in  claim 8 , wherein the fabric pieces are bonded together by applying a latex adhesive and the temporary attachment is created by melting the latex adhesive using an ultrasonic wave. 
   
   
     12. A method as in  claim 8 , wherein the penetrating hole for inserting a needle serves as a hole for a valve allowing compressed air to be introduced into the bladder. 
   
   
     13. A ball for a ball game manufactured in accordance with the method of  claim 8 . 
   
   
     14. A ball for ball game as in  claim 5 , wherein the fabric pieces comprise a shape selected from the group consisting of a pentagon, a hexagon, and combinations thereof. 
   
   
     15. A ball for ball game as in  claim 5 , wherein the fabric pieces comprise a shape selected from the group consisting of a triangle, a pentagon, and combinations thereof. 
   
   
     16. A ball for ball game as in  claim 5 , wherein the fabric layer is formed of a laminate of two woven fabrics arranged such that respective warps of the two woven fabrics are perpendicular. 
   
   
     17. A ball for ball game as in  claim 5 , wherein at least one of the fabric pieces has a center line and at least one of a warp line and a weft line which corresponds with one of three reference circles on a spherical surface of the fabric layer, any one of the three reference circles being perpendicular to the other two reference circles. 
   
   
     18. A ball for ball game as in  claim 17 , wherein the fabric layer includes a first fabric piece arranged in such a manner that at least one of the warp line and the weft line is formed along one of the three reference circles and a second fabric piece arranged in the center of a triangular region formed by the three reference circles.